Users browsing the Internet will often encounter advertisements on the web pages that they access. Internet advertising has become big business with companies scrambling to find ways to make their advertisements appear most prominently on web pages, particularly the web pages that users most often access.
One way for companies to get an edge over their competitors is to find out what web sites are the most popular and to determine how the visibility of their advertisements on these web sites compare to those of their competitors. Some companies may employ individuals to look at advertisements appearing on a random set of web pages for a web site and then perform some manual calculation to determine the company's visibility on that web site. This technique is not only time consuming, but is often very inaccurate since the random set of web pages may include web pages that users rarely access.